Cut energy consumption and improve safety
October 2017, Pneumatics & Hydraulics
SMC Pneumatics has developed a series of standby valve solutions which can be incorporated into a system to reduce energy consumption, especially during brief, recurring equipment stoppages.
With safety and energy efficiency in mind, the VEX1500/1700 Power Valves help to reduce equipment pressure loss during downtime, lowering the amount of compressed air lost due to leaks at full operating pressure. Once the equipment is turned on again, it returns to full operating pressure from standby within a matter of seconds.
SMC Pneumatics product manager, Brian Abbott, explains that interruptions in industrial processes are the rule, not the exception. “Standby mode pays off most with short, frequent breaks. Numerous causes for standby mode include tool changes, shift changes, planned or unplanned maintenance and, of course, equipment malfunctions.”
With most industrial processes requiring a standby mode, SMC’s standby valve solution can be designed to form part of a system to help lower energy costs when machines are stopped for longer periods, such as overnight or over the weekend.
“All the loads remain pressurised, albeit at a lower pressure, and maintain a defined position,” adds Abbott. “This lowers leakage losses and compressed air consumption during equipment start-up.”
Costs cut up to 70% in practice
“Overseas, data has been collected in customer applications which show that the VEX solution offers significant cost savings,” says Abbott. “For example, a trial was run in which a keg filling and washing machine was equipped with a VEX1500 standby valve at a beer brewery. The machine runs for three days a week and cleans itself automatically at night. Unfortunately, leaks in the system lose around 250 litres of compressed air per minute. We adjusted the VEX valve to reduce system pressure to 2 bar and keep it there during breaks. That minimises the pressure loss and at the same time, the system starts up within seconds when regular operations resume. Measurements taken on this system have shown potential savings in excess of 70%.”
Abbott elaborates on the savings experienced with another application story from an international car manufacturer. “A car maker operates a machine in its car body construction unit 24 hours a day, 251-plus days a year. The operating pressure is 6 bar, but the VEX1700 standby valves reduce the pressure to 2 bar during breaks. This approach eliminated nearly 90% of the compressed air lost during these breaks.
The VEX1500/1700 standby valves perform three functions, namely: vent, shut down and hold. The series is engineered for an operating pressure range of 0,05 to 9 bar and can remain in standby mode between 0,5 and 9 bar. The optimum standby pressure is around 3,5 bar.